Serum Zonulin in HBV-Associated Chronic Hepatitis, Liver Cirrhosis, and Hepatocellular Carcinoma

Plasma proteomic profiles of patients with HIV infection and coinfection with hepatitis B/C virus undergoing anti‑retroviral therapy

Chronic liver disease is becoming a leading cause of illness and mortality in patients living with human immunodeficiency virus (HIV; PLWH) undergoing suppressive anti-retroviral therapy. Its primary etiology is coinfection with hepatitis B and C virus (HBV and HCV, respectively). Chronic liver inflammation and fibrosis can potentially lead to the development of hepatocellular carcinoma (HCC). Therefore, monitoring of the disease progression in PLWH is required. The present study aimed to explore plasma protein profiles of PLWH and those coinfected with HBV and HCV using shotgun proteomics. HIV-monoinfected, HIV/HBV-coinfected, HIV/HCV-coinfected and uninfected control individuals were recruited. Patients in the three virus-infected groups had significantly higher levels of liver fibrosis indices (fibrosis-4 score and aspartate aminotransferase to platelet ratio index) compared with the control group. Liquid chromatography-tandem mass spectrometry analysis of plasma samples identified 1,074 proteins that were differentially expressed, where subsequent partial least squares-discriminant analysis model demonstrated clear clustering of proteomes from the four sample groups; 18 proteins that were significantly differentially expressed. Heatmap analysis identified two main groups of proteins, six proteins being upregulated only in the HIV/HBV-coinfection group and 10 proteins downregulated in all three virally infected groups. STITCH 5.0 analysis predicted an interaction network containing two identified proteins in the latter group, specifically ubiquitin interaction motif-containing 1 (UIMC1) and haptoglobin (HP), which are part of the profibrogenic TGF-1β/SMAD, inflammatory TNF and tumor suppressor BRCA1 pathways. Expression levels of UIMC1 and HP were significantly lower in HIV-infected groups compared with those in uninfected controls. Altogether, these proteomics data provide protein expression profiles potentially associated with HIV infection and coinfection with HBV/HCV, which may be applied to predict progression to advanced liver disease or HCC in PLWH.

Presepsin as a biomarker of bacterial translocation and an indicator for the prescription of probiotics in cirrhosis

BACKGROUND

The gut-liver axis and bacterial translocation are important in cirrhosis, but there is no available universal biomarker of cellular bacterial translocation, for which presepsin may be a candidate.

AIM

To evaluate the relationship of the blood presepsin levels with the state of the gut microbiota in cirrhosis in the absence of obvious infection.

METHODS

This study included 48 patients with Child-Pugh cirrhosis classes B and C and 15 healthy controls. The fecal microbiome was assessed using 16S rRNA gene sequencing. Plasma levels of presepsin were measured. A total of 22 patients received a probiotic (Saccharomyces boulardii) for 3 months.

RESULTS

Presepsin levels were higher in patients with cirrhosis than in healthy individuals [342 (91-2875) vs 120 (102-141) pg/mL; P = 0.048]. Patients with elevated presepsin levels accounted for 56.3% of all included patients. They had lower levels of serum albumin and higher levels of serum total bilirubin and overall severity of cirrhosis as assessed using the Child-Pugh scale. Patients with elevated presepsin levels had an increased abundance of the main taxa responsible for bacterial translocation, namely Bacilli and Proteobacteria (including the main class Gammaproteobacteria and the minor taxa Xanthobacteraceae and Stenotrophomonas), and a low abundance of bacteria from the family Lachnospiraceae (including the minor genus Fusicatenibacter), which produce short-chain fatty acids that have a positive effect on intestinal barrier function. The presepsin level directly correlated with the relative abundance of Bacilli, Proteobacteria, and inversely correlated with the abundance of Lachnospiraceae and Propionibacteriaceae. After 3 months of taking the probiotic, the severity of cirrhosis on the Child-Pugh scale decreased significantly only in the group with elevated presepsin levels [from 9 (8-11) to 7 (6-9); P = 0.004], while there were no significant changes in the group with normal presepsin levels [from 8 (7-8) to 7 (6-8); P = 0.123]. A high level of presepsin before the prescription of the probiotic was an independent predictor of a greater decrease in Child-Pugh scores (P = 0.046), as well as a higher level of the Child-Pugh scale (P = 0.042), but not the C-reactive protein level (P = 0.679) according to multivariate linear regression analysis.

CONCLUSION

The level of presepsin directly correlates with the abundance in the gut microbiota of the main taxa that are substrates of bacterial translocation in cirrhosis. This biomarker, in the absence of obvious infection, seems important for assessing the state of the gut-liver axis in cirrhosis and deciding on therapy targeted at the gut microbiota in this disease.

Gut Microbiota and Bacterial Translocation in the Pathogenesis of Liver Fibrosis

Cirrhosis is the end result of liver fibrosis in chronic liver diseases. Studying the mechanisms of its development and developing measures to slow down and regress it based on this knowledge seem to be important tasks for medicine. Currently, disorders of the gut-liver axis have great importance in the pathogenesis of cirrhosis. However, gut dysbiosis, which manifests as increased proportions in the gut microbiota of Bacilli and Proteobacteria that are capable of bacterial translocation and a decreased proportion of Clostridia that strengthen the intestinal barrier, occurs even at the pre-cirrhotic stage of chronic liver disease. This leads to the development of bacterial translocation, a process by which those microbes enter the blood of the portal vein and then the liver tissue, where they activate Kupffer cells through Toll-like receptor 4. In response, the Kupffer cells produce profibrogenic cytokines, which activate hepatic stellate cells, stimulating their transformation into myofibroblasts that produce collagen and other elements of the extracellular matrix. Blocking bacterial translocation with antibiotics, probiotics, synbiotics, and other methods could slow down the progression of liver fibrosis. This was shown in a number of animal models but requires further verification in long-term randomized controlled trials with humans.

sCD14 and Intestinal Fatty Acid Binding Protein Are Elevated in the Serum of Patients With Idiopathic Anaphylaxis

BACKGROUND

Intestinal epithelial integrity compromise has been identified in gastrointestinal (GI), atopic, and autoimmune diseases.

OBJECTIVE

Episodes of idiopathic anaphylaxis (IA) are often accompanied by GI manifestations. We, therefore, sought to determine whether surrogate markers of GI permeability were aberrant in this patient population.

METHODS

Serum concentrations of zonulin, intestinal fatty acid binding protein (I-FABP), and soluble CD14 (sCD14) measured in 54 patients with IA were compared with concentrations in healthy controls (HCs); and correlated with clinical and laboratory parameters.

RESULTS

The I-FABP was elevated in sera of patients with IA compared with HCs (median 1,378.0 pg/mL vs 479.0 pg/mL, respectively; P < .001). The sCD14 was also elevated compared with HCs (median 2,017.0 ng/mL and 1,189.0 ng/mL, respectively; P < .001), whereas zonulin was comparable between patients with IA and HCs (median 49.6 ng/mL vs 52.4 ng/mL, respectively; P = .40). The I-FABP was elevated in patients with IA who experienced vomiting and/or diarrhea compared with patients with IA who did not (P = .0091).

CONCLUSIONS

The I-FABP and sCD14 are elevated in the serum of patients with IA. Elevations in these biomarkers of IA provides evidence that increased GI permeability, as is observed in other allergic conditions such as food allergy, is a common finding in those with IA and offers possible insight into the pathogenesis of this disease.

Prohaptoglobin is a possible prognostic biomarker for colorectal cancer

BACKGROUND AND AIMS

Fucosylated haptoglobin is a novel glycan biomarker for colorectal and other cancers, while the significance of its precursor, prohaptoglobin (proHp), remains to be elucidated. In this study, we investigated whether proHp can be a colorectal cancer (CRC) biomarker and the biological functions of proHp in CRC using 10-7G, a monoclonal antibody recently developed in our laboratory.

MATERIALS AND METHODS

Serum proHp level in 74 patients with CRC was semi-quantified by western blotting, and 5-year recurrence-free survival and overall survival were analyzed for groups stratified by proHp status (high vs. low). We also performed immunohistochemical analyses of 17 CRC tissue sections using 10-7G mAb. The biological functions of proHp were evaluated by overexpressing proHp in CRC cell lines.

RESULTS

Serum proHp correlated with the clinical stage and poorer prognosis of CRC. In the primary CRC sections, immune cells were stained positive for 10-7G in ∼50% of the cases. Overexpression of proHp in HCT116 human CRC cells induced epithelial-mesenchymal transition-like changes and promoted cell migration in CRC cells.

CONCLUSION

We provide evidence for the first time that proHp has potential as a prognostic biomarker for CRC and demonstrated specific biological activities of proHp.

Zonulin as a Potential Therapeutic Target in Microbiota-Gut-Brain Axis Disorders: Encouraging Results and Emerging Questions

The relationship between dysbiosis and central nervous diseases has been proved in the last 10 years. Microbial alterations cause increased intestinal permeability, and the penetration of bacterial fragment and toxins induces local and systemic inflammatory processes, affecting distant organs, including the brain. Therefore, the integrity of the intestinal epithelial barrier plays a central role in the microbiota-gut-brain axis. In this review, we discuss recent findings on zonulin, an important tight junction regulator of intestinal epithelial cells, which is assumed to play a key role in maintaining of the blood-brain barrier function. In addition to focusing on the effect of microbiome on intestinal zonulin release, we also summarize potential pharmaceutical approaches to modulate zonulin-associated pathways with larazotide acetate and other zonulin receptor agonists or antagonists. The present review also addresses the emerging issues, including the use of misleading nomenclature or the unsolved questions about the exact protein sequence of zonulin.

Food, gut barrier dysfunction, and related diseases: A new target for future individualized disease prevention and management

Dysfunction of gut barrier is known as "leaky gut" or increased intestinal permeability. Numerous recent scientific evidences showed the association between gut dysfunction and multiple gastrointestinal tract (GI) and non-GI diseases. Research also demonstrated that food plays a crucial role to cause or remedy gut dysfunction related to diseases. We reviewed recent articles from electronic databases, mainly PubMed. The data were based on animal models, cell models, and human research in vivo and in vitro models. In this comprehensive review, our aim focused on the relationship between dietary factors, intestinal permeability dysfunction, and related diseases. This review synthesizes currently available literature and is discussed in three parts: (a) the mechanism of gut barrier and function, (b) food and dietary supplements that may promote gut health, and food or medication that may alter gut function, and (c) a table that organizes the synthesized information by general mechanisms for diseases related to leaky gut/intestinal permeability and associated dietary influences. With future research, dietary intervention could be a new target for individualized disease prevention and management.

Zonulin — regulation of tight contacts in the brain and intestine — facts and hypotheses

In recent years, the interrelationship between the brain and the gut has become an area of high scientific interest. The intestine is responsible not only for digestion, as it contains millions of neurons, its own immune system, and affects the emotional and cognitive processes. The relationship between the gut and the brain suggests that the processes carried out by the gut microbiota play a significant role in the regulation of brain function, and vice versa. A special role here is played by intercellular tight junctions (TJ), where the zonulin protein holds an important place. Zonulin, an unprocessed precursor of mature haptoglobin, is the only physiological modulator of intercellular TJ that can reversibly regulate the permeability of the intestinal (IB) and blood-brain (BBB) barriers in the human body. BBB disruption and altered microbiota composition are associated with many diseases, including neurological disorders and neuroinflammation. That is, there is a gut-brain axis (GBA) — a communication system through which the brain modulates the functions of the gastrointestinal tract (GIT) and vice versa. GBA is based on neuronal, endocrine, and immunological mechanisms that are interconnected at the organismal, organ, cellular, and molecular levels.

Gut microbiota alteration and modulation in hepatitis B virus-related fibrosis and complications: Molecular mechanisms and therapeutic inventions

Hepatitis B virus (HBV) has posed a threat to public health, mainly resulting in liver damage. With long-term accumulation of extracellular matrix, patients with chronic hepatitis B are at high risk of developing into liver fibrosis and cirrhosis and even life-threatening hepatic carcinoma. The occurrence of complications such as spontaneous bacterial peritonitis and hepatic encephalopathy greatly increases disability and mortality. With deeper understanding of the bidirectional interaction between the liver and the gut (gut-liver axis), there is a growing consensus that the human health closely relates to the gut microbiota. Supported by animal and human studies, the gut microbiota alters as the HBV-related liver fibrosis initials and progresses, characterized as the decrease of the ratio between “good” and “potentially pathogenic” microbes. When the primary disease is controlled via antiviral treatment, the gut microbiota dysfunction tends to be improved. Conversely, the recovery of gut microbiota can promote the regression of liver fibrosis. Therapeutic strategies targeted on gut microbiota (rifaximin, probiotics, engineered probiotics and fecal microbiota transplantation) have been applied to animal models and patients, obtaining satisfactory results.

Identification and Validation of Novel Biomarkers for Hepatocellular Carcinoma, Liver Fibrosis/Cirrhosis and Chronic Hepatitis B via Transcriptome Sequencing Technology

Purpose

The aim of this study was to identify and validate novel biomarkers for distinguishing among hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC), liver fibrosis/liver cirrhosis (LF/LC) and chronic hepatitis B (CHB).

Patients and Methods

Transcriptomic sequencing was conducted on the liver tissues of 5 patients with HCC, 5 patients with LF/LC, 5 patients with CHB, and 4 healthy controls. The expression levels of selected mRNAs and proteins were assessed by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemical (IHC) staining, and were verified in validation set (n=200) and testing set (n=400) via enzyme-linked immunosorbent assay (ELISA).

Results

A total of 9 hub mRNAs were identified by short time-series expression miner and weighted gene co-expression network analysis. Of note, the results of qRT-PCR and IHC staining demonstrated that SHC adaptor protein 1 (SHC1), SLAM family member 8 (SLAMF8), and interleukin-32 (IL-32) exhibited gradually increasing trends in the four groups. Subsequent ELISA tests on the validation cohort indicated that the plasma levels of SHC1, SLAMF8 and IL-32 also gradually increased. Furthermore, a diagnostic model APFSSI (age, PLT, ferritin, SHC1, SLAMF8 and IL-32) was established to distinguish among CHB, LF/LC and HCC. The performance of APFSSI model for discriminating CHB from healthy subjects (AUC=0.966) was much greater compared to SHC1 (AUC=0.900), SLAMF8 (AUC=0.744) and IL-32 (AUC=0.821). When distinguishing LF/LC from CHB, APFSSI was the most outstanding diagnostic parameter (AUC=0.924), which was superior to SHC1, SLAMF8 and IL-32 (AUC=0.812, 0.684 and 0.741, respectively). Likewise, APFSSI model with the greatest AUC value displayed an excellent performance for differentiating between HCC and LF/LC than other variables (SHC1, SLAMF8 and IL-32) via ROC analysis. Finally, the results in the test set were consistent with those in the validation set.

Conclusion

SHC1, SLAMF8 and IL-32 can differentiate among patients with HCC, LF/LC, CHB and healthy controls. More importantly, the APFSSI model greatly improves the diagnostic accuracy of HBV-associated liver diseases.

The role of gut microbiota in hepatitis B disease progression and treatment

Current therapeutic interventions can only suppress hepatitis B virus (HBV) replication or reduce complications without a cure. Therefore, further development of new treatment methods is critical for the global eradication of HBV. Accumulating evidence suggests that the liver and gut share an interconnected relationship referred to as the 'Gut-Liver Axis', where exchanges happen bi-directionally. The gut itself is the host to a unique microbiota profile which has metabolic, immunological, neurological and nutritional functions. Gut microbiota is not only constantly intersecting with the liver but also associated with hepatic injury when dysbiosis occurs. In recent years, there has been increased interest in gut microbiota and its implications on liver disease treatment. Progress has been made in understanding the complex relationship between chronic hepatitis B (CHB) and gut microbiota. New investigative techniques such as colony-free sequencing enabled new perspectives into this field. Mouse models and human studies revealed that HBV infection is associated with significant alteration of gut microbiota, which differ depending on the stage of CHB disease progression. Different mechanisms of the hepatic injury from gut microbiota dysbiosis have also been proposed based on findings of increased intestinal permeability to toxins, disruption of normal bacterial metabolism, and colonization of the gut by oral microbiota. New treatment methods targeting gut microbiota in CHB, such as probiotics and faecal microbiota transplant, have also gained promising results in recent years. The current review recapitulated the most recent investigations into the relationship between gut microbiota and CHB to provide research directions towards the new therapeutic target of CHB.

Molecular Immune Mechanism of Intestinal Microbiota and Their Metabolites in the Occurrence and Development of Liver Cancer

Intestinal microorganisms are closely associated with immunity, metabolism, and inflammation, and play an important role in health and diseases such as inflammatory bowel disease, diabetes, cardiovascular disease, Parkinson’s disease, and cancer. Liver cancer is one of the most fatal cancers in humans. Most of liver cancers are slowly transformed from viral hepatitis, alcoholic liver disease, and non-alcoholic fatty liver disease. However, the relationship between intestinal microbiota and their metabolites, including short-chain fatty acids, bile acids, indoles, and ethanol, and liver cancer remains unclear. Here, we summarize the molecular immune mechanism of intestinal microbiota and their metabolites in the occurrence and development of liver cancer and reveal the important role of the microbiota-gut-liver axis in liver cancer. In addition, we describe how the intestinal flora can be balanced by antibiotics, probiotics, postbiotics, and fecal bacteria transplantation to improve the treatment of liver cancer. This review describes the immunomolecular mechanism of intestinal microbiota and their metabolites in the occurrence and development of hepatic cancer and provides theoretical evidence support for future clinical practice.

Gut-liver axis in cirrhosis: Are hemodynamic changes a missing link?

Recent evidence suggests that the condition of the gut and its microbiota greatly influence the course of liver disease, especially cirrhosis. This introduces the concept of the gut–liver axis, which can be imagined as a chain connected by several links. Gut dysbiosis, small intestinal bacterial overgrowth, and intestinal barrier alteration lead to bacterial translocation, resulting in systemic inflammation. Systemic inflammation further causes vasodilation, arterial hypotension, and hyperdynamic circulation, leading to the aggravation of portal hypertension, which contributes to the development of complications of cirrhosis, resulting in a poorer prognosis. The majority of the data underlying this model were obtained initially from animal experiments, and most of these correlations were further reproduced in studies including patients with cirrhosis. However, despite the published data on the relationship of the disorders of the gut microbiota with the complications of cirrhosis and the proposed pathogenetic role of hemodynamic disorders in their development, the direct relations between gut dysbiosis and hemodynamic changes in this disease are poorly studied. They remain a missing link in the gut–liver axis and a challenge for future research.

Dysbiosis of Gut Microbiota Promotes Hepatocellular Carcinoma Progression by Regulating the Immune Response

Method

This study included 74 Chinese male patients with HCC. They were divided into early (n = 19), intermediate (n = 37), and terminal (n = 18) groups, referred to as Barcelona Clinic Liver Cancer stage 0+A, B, and C+D, respectively. Paired fecal and plasma samples were collected. Microbial composition and profiles were analyzed by 16S rRNA gene sequencing. The levels of gut damage marker (regenerating islet-derived protein 3α (REG3α)) and microbial translocation markers (soluble CD14 (sCD14), lipopolysaccharide-binding protein (LBP), peptidoglycan recognition proteins (PGRPs)) were determined in plasma samples of patients by ELISA. Twenty plasma cytokine and chemokines were determined by Luminex.

Results

In early, intermediate, and terminal groups, the abundance of the Bifidobacteriaceae family decreased significantly (3.52%, 1.55%, and 0.56%, respectively, P = 0.003), while the abundance of the Enterococcaceae family increased significantly (1.6%, 2.9%, and 13.4%, respectively, P = 0.022). Levels of REG3α and sCD14 were markedly elevated only in the terminal group compared with the early (P = 0.025 and P = 0.048) and intermediate groups (P = 0.023 and P = 0.046). The level of LBP significantly increased in the intermediate (P = 0.035) and terminal (P = 0.025) groups compared with the early group. The PGRP levels were elevated only in the terminal group compared with the early group (P = 0.018). The ratio of Enterococcaceae to Bifidobacteriaceae was significantly associated with the levels of REG3α, LBP, sCD14, and PGRPs. With HCC progression, increased levels of inflammatory cytokines accompanied by a T cell-immunosuppressive response and microbial translocation were observed.

Conclusion

Gut microbiota compositional and functional shift, together with elevated gut damage and microbial translocation, may promote HCC development by stimulating inflammatory response and suppressing T cell response.

Serum zonulin levels in patients with liver cirrhosis: Prognostic implications

BACKGROUND

Increased gut permeability and bacterial translocation play an important role in liver cirrhosis. Zonulin is a recently recognized protein involved in the disintegration of the intestinal barrier.

AIM

To investigate possible differences in serum zonulin levels among patients with different cirrhosis stages and their potential prognostic implications.

METHODS

Consecutive cirrhotic patients who attended our liver clinic were included in the study. Serum zonulin levels, clinical, radiological and biochemical data were collected at baseline. Patients who accepted participation in a regular surveillance program were followed-up for at least 12 mo.

RESULTS

We enrolled 116 cirrhotics [mean Child-Turcotte-Pugh (CTP) score: 6.2 ± 1.6; model for end-stage liver disease score: 11 ± 3.9]. The causes of cirrhosis were viral hepatitis (39%), alcohol (30%), non-alcoholic fatty liver disease (17%), and other (14%). At baseline, 53% had decompensated cirrhosis, 48% had ascites, and 32% had history of hepatic encephalopathy. Mean zonulin levels were significantly higher in patients with CTP-B class than CTP-A class (4.2 ± 2.4 ng/dL vs 3.5 ± 0.9 ng/dL, P = 0.038), with than without ascites (P = 0.006), and with than without history of encephalopathy (P = 0.011). Baseline serum zonulin levels were independently associated with the probability of decompensation at 1 year (P = 0.039), with an area under the receiving operating characteristic of 0.723 for predicting hepatic decompensation. Higher CTP score (P = 0.021) and portal vein diameter (P = 0.022) were independent predictors of mortality.

CONCLUSION

Serum zonulin levels are higher in patients with more advanced chronic liver disease and have significant prognostic value in identifying patients who will develop decompensation.

The Applicability of ADA, AFU, and LAC in the Early Diagnosis and Disease Risk Assessment of Hepatitis B-Associated Liver Cirrhosis and Hepatocellular Carcinoma

Objective: This study aimed to evaluate the applicability of adenosine deaminase (ADA), α-l-fucosidase (AFU), lactic acid (LAC), and their combined detection in the early diagnosis of chronic hepatitis B (CHB), liver cirrhosis (LC), and hepatocellular carcinoma (HCC). Methods: A retrospective analysis of hepatitis B-positive liver disease patients admitted between 2015 and 2020 was conducted. The receiver operating characteristic (ROC) curve was used to determine the diagnostic value of each indicator in LC and HCC, and binary logistic regression analysis was performed to determine the factors and risks related to the occurrence of the two conditions. Results: The levels of ADA, AFU, and LAC were significantly increased in patients with CHB, LC, and HCC (p < 0.05). The ROC curve showed that the sensitivity and specificity of ADA, AFU, LAC, and their combined detection in the CHB and LC groups as well as in the LC and HCC groups reflected different degrees of clinical value. In the CHB and LC groups, the adjusted odds ratio (OR) values of ADA, AFU, and LAC among patients in the high-level group were 3.218, 1.859, and 11.474, respectively, when the median was considered the cutoff point. When quartiles were considered the cutoff point, the OR risk values of the adjusted levels of ADA, AFU, and LAC were higher than those of the lowest-level group (Q1) (p < 0.05). In the LC and HCC groups, the adjusted OR values of ADA, AFU, and LAC among patients in the high-level group were 0.967, 2.365, and 38.368, respectively. When quartiles were considered the cutoff point, the OR risk values of AFU and LAC levels were higher than those of the lowest-level group (Q1) (p < 0.05). Conclusion: ADA, AFU, and LAC demonstrated good value in the early diagnosis of LC and HCC. The combined detection of ADA+AFU+LAC is more effective than single detection for the early diagnosis of the two conditions. ADA, AFU, and LAC can serve as risk predictors of LC, while AFU and LAC can be considered early risk predictors of HCC.

Abdominal ultrasound and alpha-foetoprotein for the diagnosis of hepatocellular carcinoma in adults with chronic liver disease

BACKGROUND

Hepatocellular carcinoma (HCC) occurs mostly in people with chronic liver disease and ranks sixth in terms of global instances of cancer, and fourth in terms of cancer deaths for men. Despite that abdominal ultrasound (US) is used as an initial test to exclude the presence of focal liver lesions and serum alpha-foetoprotein (AFP) measurement may raise suspicion of HCC occurrence, further testing to confirm diagnosis as well as staging of HCC is required. Current guidelines recommend surveillance programme using US, with or without AFP, to detect HCC in high-risk populations despite the lack of clear benefits on overall survival. Assessing the diagnostic accuracy of US and AFP may clarify whether the absence of benefit in surveillance programmes could be related to under-diagnosis. Therefore, assessment of the accuracy of these two tests for diagnosing HCC in people with chronic liver disease, not included in surveillance programmes, is needed.

OBJECTIVES

Primary: the diagnostic accuracy of US and AFP, alone or in combination, for the diagnosis of HCC of any size and at any stage in adults with chronic liver disease, either in a surveillance programme or in a clinical setting. Secondary: to assess the diagnostic accuracy of abdominal US and AFP, alone or in combination, for the diagnosis of resectable HCC; to compare the diagnostic accuracy of the individual tests versus the combination of both tests; to investigate sources of heterogeneity in the results.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Hepato-Biliary Group Diagnostic-Test-Accuracy Studies Register, Cochrane Library, MEDLINE, Embase, LILACS, Science Citation Index Expanded, until 5 June 2020. We applied no language or document-type restrictions.

SELECTION CRITERIA

Studies assessing the diagnostic accuracy of US and AFP, independently or in combination, for the diagnosis of HCC in adults with chronic liver disease, with cross-sectional and case-control designs, using one of the acceptable reference standards, such as pathology of the explanted liver, histology of resected or biopsied focal liver lesion, or typical characteristics on computed tomography, or magnetic resonance imaging, all with a six-months follow-up.

DATA COLLECTION AND ANALYSIS

We independently screened studies, extracted data, and assessed the risk of bias and applicability concerns, using the QUADAS-2 checklist. We presented the results of sensitivity and specificity, using paired forest-plots, and tabulated the results. We used a hierarchical meta-analysis model where appropriate. We presented uncertainty of the accuracy estimates using 95% confidence intervals (CIs). We double-checked all data extractions and analyses.

MAIN RESULTS

We included 373 studies. The index-test was AFP (326 studies, 144,570 participants); US (39 studies, 18,792 participants); and a combination of AFP and US (eight studies, 5454 participants). We judged at high-risk of bias all but one study. Most studies used different reference standards, often inappropriate to exclude the presence of the target condition, and the time-interval between the index test and the reference standard was rarely defined. Most studies with AFP had a case-control design. We also had major concerns for the applicability due to the characteristics of the participants. As the primary studies with AFP used different cut-offs, we performed a meta-analysis using the hierarchical-summary-receiver-operating-characteristic model, then we carried out two meta-analyses including only studies reporting the most used cut-offs: around 20 ng/mL or 200 ng/mL. AFP cut-off 20 ng/mL: for HCC (147 studies) sensitivity 60% (95% CI 58% to 62%), specificity 84% (95% CI 82% to 86%); for resectable HCC (six studies) sensitivity 65% (95% CI 62% to 68%), specificity 80% (95% CI 59% to 91%). AFP cut-off 200 ng/mL: for HCC (56 studies) sensitivity 36% (95% CI 31% to 41%), specificity 99% (95% CI 98% to 99%); for resectable HCC (two studies) one with sensitivity 4% (95% CI 0% to 19%), specificity 100% (95% CI 96% to 100%), and one with sensitivity 8% (95% CI 3% to 18%), specificity 100% (95% CI 97% to 100%). US: for HCC (39 studies) sensitivity 72% (95% CI 63% to 79%), specificity 94% (95% CI 91% to 96%); for resectable HCC (seven studies) sensitivity 53% (95% CI 38% to 67%), specificity 96% (95% CI 94% to 97%). Combination of AFP (cut-off of 20 ng/mL) and US: for HCC (six studies) sensitivity 96% (95% CI 88% to 98%), specificity 85% (95% CI 73% to 93%); for resectable HCC (two studies) one with sensitivity 89% (95% CI 73% to 97%), specificity of 83% (95% CI 76% to 88%), and one with sensitivity 79% (95% CI 54% to 94%), specificity 87% (95% CI 79% to 94%). The observed heterogeneity in the results remains mostly unexplained, and only in part referable to different cut-offs or settings (surveillance programme compared to clinical series). The sensitivity analyses, excluding studies published as abstracts, or with case-control design, showed no variation in the results. We compared the accuracy obtained from studies with AFP (cut-off around 20 ng/mL) and US: a direct comparison in 11 studies (6674 participants) showed a higher sensitivity of US (81%, 95% CI 66% to 90%) versus AFP (64%, 95% CI 56% to 71%) with similar specificity: US 92% (95% CI 83% to 97%) versus AFP 89% (95% CI 79% to 94%). A direct comparison of six studies (5044 participants) showed a higher sensitivity (96%, 95% CI 88% to 98%) of the combination of AFP and US versus US (76%, 95% CI 56% to 89%) with similar specificity: AFP and US 85% (95% CI 73% to 92%) versus US 93% (95% CI 80% to 98%).

AUTHORS' CONCLUSIONS

In the clinical pathway for the diagnosis of HCC in adults, AFP and US, singularly or in combination, have the role of triage-tests. We found that using AFP, with 20 ng/mL as a cut-off, about 40% of HCC occurrences would be missed, and with US alone, more than a quarter. The combination of the two tests showed the highest sensitivity and less than 5% of HCC occurrences would be missed with about 15% of false-positive results. The uncertainty resulting from the poor study quality and the heterogeneity of included studies limit our ability to confidently draw conclusions based on our results.

Sugar Alcohols Have a Key Role in Pathogenesis of Chronic Liver Disease and Hepatocellular Carcinoma in Whole Blood and Liver Tissues

The major risk factors for hepatocellular carcinoma (HCC) are hepatitis C and B viral infections that proceed to Chronic Liver Disease (CLD). Yet, the early diagnosis and treatment of HCC are challenging because the pathogenesis of HCC is not fully defined. To better understand the onset and development of HCC, untargeted GC-TOF MS metabolomics data were acquired from resected human HCC tissues and their paired non-tumor hepatic tissues (n = 46). Blood samples of the same HCC subjects (n = 23) were compared to CLD (n = 15) and healthy control (n = 15) blood samples. The participants were recruited from the National Liver Institute in Egypt. The GC-TOF MS data yielded 194 structurally annotated compounds. The most strikingly significant alteration was found for the class of sugar alcohols that were up-regulated in blood of HCC patients compared to CLD subjects (p < 2.4 × 10⁻¹²) and CLD compared to healthy controls (p = 4.1 × 10⁻⁷). In HCC tissues, sugar alcohols were the most significant (p < 1 × 10⁻⁶) class differentiating resected HCC tissues from non-malignant hepatic tissues for all HCC patients. Alteration of sugar alcohol levels in liver tissues also defined early-stage HCC from their paired non-malignant hepatic tissues (p = 2.7 × 10⁻⁶). In blood, sugar alcohols differentiated HCC from CLD subjects with an ROC-curve of 0.875 compared to 0.685 for the classic HCC biomarker alpha-fetoprotein. Blood sugar alcohol levels steadily increased from healthy controls to CLD to early stages of HCC and finally, to late-stage HCC patients. The increase in sugar alcohol levels indicates a role of aldo-keto reductases in the pathogenesis of HCC, possibly opening novel diagnostic and therapeutic options after in-depth validation.

All disease begins in the (leaky) gut: role of zonulin-mediated gut permeability in the pathogenesis of some chronic inflammatory diseases

Improved hygiene leading to reduced exposure to microorganisms has been implicated as one possible cause for the recent "epidemic" of chronic inflammatory diseases (CIDs) in industrialized countries. That is the essence of the hygiene hypothesis that argues that rising incidence of CIDs may be, at least in part, the result of lifestyle and environmental changes that have made us too "clean" for our own good, so causing changes in our microbiota. Apart from genetic makeup and exposure to environmental triggers, inappropriate increase in intestinal permeability (which may be influenced by the composition of the gut microbiota), a "hyper-belligerent" immune system responsible for the tolerance-immune response balance, and the composition of gut microbiome and its epigenetic influence on the host genomic expression have been identified as three additional elements in causing CIDs. During the past decade, a growing number of publications have focused on human genetics, the gut microbiome, and proteomics, suggesting that loss of mucosal barrier function, particularly in the gastrointestinal tract, may substantially affect antigen trafficking, ultimately influencing the close bidirectional interaction between gut microbiome and our immune system. This cross-talk is highly influential in shaping the host gut immune system function and ultimately shifting genetic predisposition to clinical outcome. This observation led to a re-visitation of the possible causes of CIDs epidemics, suggesting a key pathogenic role of gut permeability. Pre-clinical and clinical studies have shown that the zonulin family, a group of proteins modulating gut permeability, is implicated in a variety of CIDs, including autoimmune, infective, metabolic, and tumoral diseases. These data offer novel therapeutic targets for a variety of CIDs in which the zonulin pathway is implicated in their pathogenesis.